Japanese Patent Application Laid-Open Publication No. 2017-129528 (Patent Document 1) discloses a current sensing circuit including a sensing resistor for sensing a current of a solenoid valve, an amplifier unit for amplifying a sensed voltage of the sensing resistor, an AD converter for outputting a sensed current value as it digitally converts an output of the amplifier unit, and a correction unit. The correction unit includes a memory for memorizing information of a temperature characteristics of the sensed current value occurring due to temperature characteristics of a reference current (reference voltage) of the AD converter and a temperature sensor, the correction unit correcting the sensed current value from the AD converter based on a sensed result of a temperature sensor and information of the memory unit.
Japanese Patent Publication No. 5590240 (Patent Document 2) discloses a configuration including a power semiconductor device having a sensing function and including a main transistor, a sensing transistor, and a temperature sensing diode, a current-voltage converting circuit for converting a current of the sensing transistor into a voltage, a variable voltage source for adjusting a sensing voltage from the current-voltage converting circuit, and a correction operating unit. The correction operating unit corrects variations of a current sense ratio in accordance with temperature by controlling the variable voltage source by a calculating result obtained by an operation with a set value preliminarily saved in a memory.
Japanese Patent Application Laid-Open Publication No. 2011-97434 (Patent Document 3) discloses a current-controlling semiconductor element including a high-side MOSFET coupled to a solenoid, a current-voltage converting circuit for sensing a current of the high-side MOSFET via a sensing MOSFET and a sensing resistor, an AD converter for digitally converting a voltage converted by the current-voltage converting circuit, a reference-current generating circuit, a correction-value calculating circuit, and a temperature sensor. The correction-value calculating circuit activates a correction-value calculating operation for correcting an influence of temperature variations of the sensing resistor and so forth when the temperature sensed by the temperature sensor is varied by more than a predetermined temperature. In the correction-value calculating operation, a correction value for correcting a digital value from the AD converter is calculated by measuring a constant current from the reference-current generating circuit using the AD converter via the current-voltage converting circuit.